I’ve been searching the web for a solution of my uploader in WordPress. It gives a http error when uploading png images, in the class-wp-image-editor-imagick.php file in the load function:$this->image = new Imagick( $this->file );

WordPress version is 4.3.1
ImageMagick version 6.5.4-7
PHP Version 5.4.42

No idea if it is the combination of this can be the problem but I found a partial solution for the problem. In WordPress, go to Appearence -> Editor and open the functions.php file. Now enter this code snippet at the bottom: